Furnace wall construction



Oct. 27, 1942. M, 1 WEBSTER FURNACE :wALn -coNsTRUcTIQn Filed Oct. 14, 1940 Patented Oct. 27, 1942 f l UNITED j STATES PATENT OFFICE FURNACE WALL CONSTRUCTION Maury L. Webster, Los Angeles, Calif.`

Application October 14, 19405 Serial No. 361,126

v 4 claims. (c1. 724-4191) present invention may be considered as an improvement on or a further development of my patent for Wall construction'No. 1,880,561, issued October 4, 1932. x

This patent among other features disclosed the bonding ofthe refractory brick or blocks of theinside lining of `the furnace and the outside .common blocks or bricks, these latter havingv `a much thicker bed of'the conventional mortar, In addition, my; patent presented metal reenforcements worked into the common brick or blocks binding the wall to an exterior metal ccnwhen the furnace is cool employs tie rods con-` necting metal posts or similar structures at the end of `the wall. These tie rods may be periodi.- cally tightened by threading up a nut at one or both ends in order to `forcibly pull the wall back to theorginal length. Manifestly this construction. each time the Wall expands there develops a stretch of the tie rod. Mostly this is Within the elastic limit of the rod so that when the wall cools the tie rod Will return the wall-to its original length. Howevenin practice it is found that the tie rods stretch and hence require the periodical tightening of the nuts to exert the proper tension and hence the inward pull on the ends of the common brick facing of the wall.

In accordance with my present' invention I embed longitudinal reenforcements of metal in the common block or ccmmonbrick in aportion of the furnace wall spaced from the refractoryY portion thereof. Such reenforcement is bonded with the commonbrick portion of the wall in partlby being embedded in. the mortar joint. This metal reenforcement has substantially the ,same coefficient of expansion of the common blocks 4or bricks and hence when the `wall eX- pands lengthwise the reenforcement metal also expands. However, `where thelbricks are not reenforced in `this manner with the tie rod binding omitted the mortar joints do notrdevelop a `tenfsilev pull to return the bricks to their-original position and bring back` the wall to its original ,55.v ,rows of brickson'the outerface` of the wall are length. Where the reenforcement of this invention is present and the wall contracts on cooling the wall returns to its normal and original position as to length. This longitudinal reenforcement also reacts when the brick-work of the common bricks is expanded longitudinally due to the stresses developed by the heated refractories even if'fthe temperature of the common bricks is insufficient to cause a longitudinal expansion. In this case 'the metal reenforcementundergoes a stretch and when this is within the elastic limit of the metal, returns to its original length when the wall cools and therefore again contracts the wall. A preferred type of longitudinal reenforcement is a metal and Wire fabric formed with a plurality of longitudinal;y strands as for instance three wires spaced apart and intersected byltransverse connecting wires. These need not belvery close together but to purchase material now on the market I utilize the conventional square or rectangular mesh wire fabric. These reenforcements are made in long strips and are embedded in the mortar joint between adjacent tiers of the common block or j brick. i

Another feature of my invention is the employmen'tof a vertical reen'forcement of the com` mon blocks or bricks by use of vertical reenforcement rods embedded in the vertical mortar joints of thecom'mon brick portion of the wall. These i vertical rods `pass through the different layers ofthe horizontal reenforcement strips and aid' materially inbondin'g the horizontal reenforcement tothe common brick4 portion of the Wall. The vertical reenforcement by having the rods placed `in alignment transversely to the wall in addition develop a reenforcernent restraining the wall from bulging between .the top and bottom. They also act to restrain the wall from vertical expansion. In addition the `use `of the two types of reenforcement withthe types of joints `for the common and thel refractory bricks produces' a much lighter weight wall for the same strength andA refractory properties than that of my pati ent abovenoted and theordinary practice.

` AV further object and featureof my invention involves a supporting frame engaging the bricks or blocks of the wall'at different heighths be' tween the top and the bottom, this involving an outside supporting structure with columns and horizontalsupporting` members engaging outside or common brick or blocks. `These horizontal members may be vangles each with a horizontal Iiange fitting in the-mortar joint, therefore asl supported at tiers spaced apart vertically as on narrow ledges, a supporting member is provided which carries a good deal of the weight of the brick equipment to a distance between the various ledges. This is due to the bonding of the bricks of both the refractories and the common so that the diagonally downward thrust from the inside of the wall to the outside is transferred to a ledge. A further object and feature of this construction in giving an individual support isr between the ledge type of supports on the outside l of the wall.

Another characteristic of my invention is building up the wall with a light weight type of refractory brick having a composition such as that with sawdust incorporated therein which burns out leaving a large number of hollow cells. With this I use a quick setting cement mortar.

My invention is illustrated in connection with the accompanying drawing, in which:

Fig. 1 is a vertical section through a furnace wall as to a portion of the wall and may be considered as taken on the section line I-I of Fig. 2 in the direction of the arrows. This shows typical mortar and cement bedding for the common and refractory bricks but is not intended to define a particular line up or section of individual bricks.

Fig. 2 is a horizontal section taken on the line 2 2 of Fig. 1 in the direction of the arrows. This omits indication of particular bricks but shows the general overlapping line between the common and the refractory bricks to secure bonding through the wall.

In the above illustration in Fig. 1 the bricks or blocks are illustrated as set up somewhat in the manner shown in my Patent No. 1,880,561 as above noted. In this the refractory blocks or bricks are designated by the numeral II on the inside of the wall and the common bricks on the outside by the numeral I2. The refractory bricks are embedded in mortar I3 preferably made of fire clay mixed with water to a desired consistency to space the bricks of the various tiers the desired distance apart. The common bricks are usually slightly thinner than the refractory bricks and thus require a thicker mortar joint indicated at I4 which may be made of a quick drying cement mortar such as that made incorporating calcium chloride and Portland cement. In the illustration the wall may be considered as having a series of tiers I5 in which the common and the refractory brick form each tier. 'I'hese are built up with headers and stretchers in the conventional manner however in each tier the refractory and the common bricks are interbonded as indicated by the dotted line I6 of Fig. 2.

In order to develop the support for different tiers of bricks I have provided a series of posts 20, these being shown as I-beams spaced apart a suitable distance and being of sufcient length to extend from the foundation at the bottom to the top of the wall. As the wall is built up, a series of supporting beams 2| are utilized. These are illustrated as angles having a horizontal ange 22 fitting in a mortar joint between com- 75 mon bricks of a lower and an upper tier. The vertical flange 23 is indicated as secured to the flange of the I-beam by a bolt 24 or the like. The horizontal flanges may be considered as forming a horizontal ledge. These ledges are spaced the desired distance. apart vertically and as shown in the illustration of Fig. 1 as six tiers apart. Due to the bonding of the brick, the components of pressure have a. diagonal line of thrust due to the bonding extending for instance in a diagonal sloping line from each ledge upwardly towards the inside face of the nre wall. These ledges of course do not carry the full weight of the complete wall or the full weight of the brick between the different ledges spaced vertically. However a considerable portion of the weight of the amount of brick between ledges is supported or partly supported by each ledge. 'I'his gives a type of support so that the inward bulge due to the expansion of the refractory bricks between the top and the bottom of the wall is broken up into a series of small bulges each of approximately the length of the vertical distance from` one ledge to the next above although these bulgesdo not necessarily coincide with the particular number of tiers between any two ledges. posts 20 and the angles or other structures forming the ledges are not subject to heat, there is comparatively little expansion and contraction of' these metal supporting structures and as the out'- side common bricks have but little expansion or contraction due to temperature changes, the mortar binding the common bricks does not disintegrate. However the re clay mortar or bedding of the refractory bricks of course more or lessv disintegrates as in the ordinary type of furnace construction.

ment assembly indicated at 3U. longitudinal rods or wire 3| which extend lengthwise of the wall and bedded in mortar joints of` the outside or common brick. In order to maintain these rods at the correct distance apart I preferably employ transverse connecting wires 32 welded or otherwise secured to the wires or rods 3l. In fact, a simple way to secure this type of construction is by the use of rectangulary wire mesh fabric slit to provide two or three longitudinal wires however if the material is made up especially for the work, the transverse connectingI wires 32 may be spaced a considerable distance apart. wire at the end of the re wall be secured to an outside structure.

The functional action of the horizontal reinforcement is substantially as follows: When the furnace is brought up to its operating temperature and maintained at this temperature for a considerable length of time, heat is transferred from the refractory lining outwardly to the common bricks although manifestly not t0 such a high temperature. The horizontal reinforcement becomes heated in proportion as the common bricks rise in temperature. I have found that the expansion and contraction of the horizontal reinforcement rods or wires is about equivalent' to that of the common brick including the mortar joints so that there is no breaking of the bond between the reinforcement rods or wires and the mortar of the joints. refractory lining expands on increase andvmaintenance of high temperature causing the whole As they It is not necessary that the ends of thev As is well known, the' pansion the metal longitudinal reinforcement rods 3| expand equally with the furnace, that is, the outer common brick but as the common brick are forced outwardly in a longitudinal direction due to the bonding with the refractory lining, the lengthwise wires or rods are placed under a tension and may actually stretch to a certain extent.

There is no particular harm or disadvantage in the lengthwise expansion of the wall while the furnace is in operation and the wall is under the usual high working temperature. When the furnace cools however if there are no means for again pulling or forcing the' wall back to its original position as regards its length, it would be left in the longitudinally expanded condition for although the individual refractory bricks will cool or contract as will the common bricks, there is no tensile bond for the respective tiers of bricks. However the horizontal reinforcement 30 is not expanded or stretched beyond its elastic limit. By this construction therefore the contraction of the horizontal rods 3| due to loss of heat from a relatively high to a moderate temperature produces a pulling action on the common brick and in additionthe return of the rods from a stretched to a normal length also reacts in this same manner, hence the wall when cooled practically always returns to its original length as long as the bricks or blocks remain intact.

The vertical reinforcement indicated at G is by means of a series of vertical rods 4l. These ,i

bed in the vertical mortar joints of the common brick. Although three rods are shown in a row from the front towards the rear, these may be any number desired. The brick mason setting up the wall may easily make his vertical joints to accommodate these rods. They need not be attached in any manner to the horizontal reinforcement b-ut these rods act as Vertical reinforcement members restraining any tendency to bulge of the comman brick due to thrust action by the expanding refractors, that is, bulges which might develop between the top and bottom of the wall outwardly.

Various changes may be made in the details of the construction without departing from the spirit or scope of the invention as deiined by the appended claims.

Iclaim:

1. A furnace wall construction having outer common bricks and inner refractory bricks, the common bricks and refractory bricks being arranged in interlocking relationship vertically as well as horizontally, and metal rods extending' lengthwise through the common brick portion of the wall adapted to be stretched or expanded when the wall is heated and serving to contract the wall lengthwise upon cooling of the wall to return it to substantially its initial condition.

2. A furnace Wall construction having outer tiers of common bricks and inner tiers of refractory bricks, the common bricks and refractory bricks being arranged in interlocking relationship in their corresponding tiers, and in interlocking relationship in a vertical direction, and metal rods extending lengthwise through the common bricks portion of the wall adapted to be stretched or expanded when the wall is heated and serving to contract the wall lengthwise upon cooling' of the wall to return it to substantially its initial condition, said rods being arranged in the joints between the common bricks, and transverse rods connecting the longitudinallyl extending rods in the joints in which they are disposed.

3. A furnace wall construction having outer common bricks and inner refractory bricks, the common bricks and refractory bricks being arranged in interlocking relationship both horizontally and vertically, supporting columns arranged adjacent the outer side of the wall, means providing ledges on the columns extending into the common brick portion of the wall and longitudinally extending metal rods embedded in the mortar joints between the common bricks adapted to be stretched or expanded upon heating of the wall and serving to contract the common brick portion of the wall on cooling.

4. A furnace wall construction having outer common bricks and inner refractory bricks, the

common bricks and refractory bricks being arranged in interlocking relationship both horizontally and vertically, supporting columns arranged adjacent the outer side of the wall, means providing ledges on the columns extending into the common brick portion of the wall and longitudinally extending metal rods embedded in the mortar joints between the common bricks adapted to be stretched or expanded upon heating of the Wall andserving to contract the common brick portion of the wall on cooling, and transverse rods connecting the longitudinal rods in the joints in which they are disposed.

MAURY L. WEBSTER. 

